Re: [PATCH] mm: mempolicy: fix the wrong return value and potential pages leak of mbind

[Andrew Morton]

On Wed, 30 Oct 2019 11:14:58 -0700 Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx> wrote:

> On 10/30/19 9:58 AM, Yang Shi wrote:
> > The commit d883544515aa ("mm: mempolicy: make the behavior consistent
> > when MPOL_MF_MOVE* and MPOL_MF_STRICT were specified") fixed the return
> > value of mbind() for a couple of corner cases.  But, it altered the
> > errno for some other cases, for example, mbind() should return -EFAULT
> > when part or all of the memory range specified by nodemask and maxnode
> > points  outside your accessible address space, or there was an unmapped
> > hole in the specified memory range specified by addr and len.
> >
> > Fixed this by preserving the errno returned by queue_pages_range().
> > And, the pagelist may be not empty even though queue_pages_range()
> > returns error, put the pages back to LRU since mbind_range() is not called
> > to really apply the policy so those pages should not be migrated, this
> > is also the old behavior before the problematic commit.
> Forgot fixes tag.
> 
> Fixes: d883544515aa ("mm: mempolicy: make the behavior consistent when 
> MPOL_MF_MOVE* and MPOL_MF_STRICT were specified")

What's the relationship between this patch and
http://lkml.kernel.org/r/201910291756045288126@xxxxxxxxx?